Ski-bob with rear ski runner forwardly suspended



p 1970 G. E. GARCIA 3,526,412

SKI-BOB WITH REAR SKI RUNNER FORWARDLY SUSPENDED Filed July 26. 1968 3Sheets$heet 1 EO/PGE E. GARC/A 6 INVENTOR 4 r U 34 ////A BY 1- 5 24 3ATTORNf) Sept. 1, 1970 G. E. GARCIA 3,526,412

SKI-BOB WITH REAR SKI RUNNER FORWAHDLY SUSPENDED 3 Sheets-Sheet 2 FiledJuly 26, 1968 GEORGE E. GARCIA [NVENTOR 46r I 55b 4% .1. ll 41 I I HZ 7ATTORNEY SKI-BOB WITH REAR SKI RUNNER FORWARDLY SUSPENDED Filed July 26,1968 3 Sheets-Sheet a 46a GEORGE E. GARC/A INVENTUR v 4Hr ATTORNEYUnited States Patent 3,526,412 SKI-BOB WITH REAR SKI RUNNER FORWARDLYSUSPENDED George E. Garcia, Houston, Tex. (2370 Broadway St., SanFrancisco, Calif. 94115) Filed July 26, 1968, Ser. No. 748,077 Int. Cl.B26b 13/04 US. Cl. 280-16 9 Claims ABSTRACT OF THE DISCLOSURE Theski-bob comprises a forward ski runner, a steering post connectedthereto to pivot in an upright longitudinal plane, a rear ski runner, aframe with forward part pivotally connected to the steering post forframe to swing across direction of ski-bob travel, and with frame rearpart connected to the rear ski runner to pivot in an uprightlongitudinal plane. Thus, with the forward, upwardly curved part of therear ski runner yieldably connected to the frame, the ski-bob mayclosely follow a track undulatory in elevation and curved in plan view.

The invention relates to a ski-bob that has the upwardly curved leadingpart of a rear ski runner yieldably disposed with relation to the frame,thus enabling the skibob more closely to follow a track that isundulatory in elevation and curved in some degree in plan view, wherebythe track is not broken up over its undulations as in the case ofconventional ski-bobs having a single ski runner, or a rear ski runnerwith a leading part that is substantially rigidly connected to theframe.

As a primary object the invention provides an inventive ski-bobconstruction with a rear ski runner having its leading part yieldablydisposed with relation to the frame whereby the ski-bob may more closelyfollow a track that may be undulatory in elevation and curved in degreein plan view.

It is also an important object of the invention to provide a ski-bob ofthis class with lower end of steering post and lower end of rear framepart both leaf spring connected to respective transverse pivots acrossrespective forward and rear ski runners.

It is yet another and important object of the invention to provide aski-bob of this class with the leading part of the rear ski-runnervariously yield-ably connectable to the frame, as by an elastic cordconnecting it to the forward part of the frame near the lower endthereof, or to the central part of the frame thereabove.

It is also another and important object of the invention to provide aski-bob of this class in which the seat is forwardly connected to theupper, central part of the frame, with the rear part of the seat beingyieldably supported by shock absorber means disposed between seat andrear ski runner.

It is still another and further object of the invention to provide aski-bob of this class which may be easily assembled with a minimumnumber of parts over conventional ski-bob combinations, but in mannerthat the assembled ski-bob may more readily follow in undulatory trackin elevation that is curved in plan view.

Other and further objects will be apparent when the specification isconsidered in connection with the drawings, in which:

FIG. 1 is an isometric view of one embodiment of the invention withleading part of rear ski runner shown, partially diagrammatically,connected in yieldably manner, to the lower end of the forward part ofthe frame;

FIG. 2 is an elevational view of a ski-bob constructed substantially incorrespondence with FIG. 1, advancing over a track undulation;

ice

FIG. 3 is an elevational view of the ski-bob shown in FIG. 2, with adepression between undulations being traversed at the point when theski-bob is disposed centrally thereover;

FIG. 4 is a development view showing the leaf spring part of the lowerrear frame, together with the yoke of the lower shock absorber in theirrelationships for assembly to the rear ski runner;

FIG. 5 is an enlarged, longitudinal, sectional elevational view ofdetails of the pivotal connection of the lower part of the forward frameto the lower part of steering post, and of steering post lower partpivotal connection by leaf spring to forward ski runner;

FIG. 6 is an elevational view of a modification of the ski-bob shown inFIGS. 2 and 3, and which is illustrative of selective seat adjustment;

FIG. 7 is an enlarged elevational view of the yeildable connectionconstruction between lower end of forward frame part and leading part ofrear ski runner, such construction being shown in smaller scale in FIG.6;

FIG. 8 is an elevational view of another modification of the ski-bobshown in FIGS. 2 and 3, in which an elastic cord establishes yieldablerelationship between frame and rear ski runner;

FIG. 9 is an elevational view of an alternate construction forestablishing yieldable relationship between frame and rear ski runner;

FIG. 10 is an elevational view of still another arrangement by whichelastic cords establish yieldable relationship between frame and rearski runner;

FIG. 11 is an enlarged detailed sectional elevational view of the shockabsorber connection shown to smaller scale in FIGS. 8, 9 and 10, betweenrear end of seat and rear ski runner;

FIG. 12 is an enlarged detailed, transverse sectional elevational viewtaken along line 12-12 of FIG. 11;

FIG. 13 is a sectional elevational view of the housed spring connection,as shown in smaller scale between leading part of rear ski runner, andupper central frame parts, in FIG. 9; and

FIG. 14 is a longitudinal elevational view showing an alternativearrangement for yieldable connection frame and shock absorber to rearski runner.

Beginning about 1891 in America, a ski-runner was first substituted forthe front wheel of a bicycle with vertical supporters for sled-runnersbeing attached on each side of the back axle, to comprise a snowbicycle, see US. Pat. No. 473,434, for Ice-Velocipede. Similar vehiclesappeared in America and Europe about the turn of the century, termedsingle-track guidable sleds. By 1910 the Swiss Mongoleit was developed,but only usable on steep snow-tracks or channels with long runs. Aprimitive Skivelon followed, used mostly by bakers-apprentices andmailmen in the Grindlewald. By 1950 a much lower ski-bob type was in usein Bavaria with no wheels or sled-runners, but with front and rear skirunners connected to an oval frame, the riders feet being encased inseparate foot attachments so heels can be applied to brake speed oninclines.

In the modern forms of ski-bobs, which are currently of widelyincreasing popularity, persons of all ages may participate in theirusage. They are less dangerous and can be safely enjoyed, notnecessarily by persons of strength and of athletic prowess, but by thoseof average, or even lesser strength than the norm. Thus their appealtends to be more universal than the conventional ice skis,conventionally associated with skilled athletes, and compentitive icefield events.

There still be be said to exist an objection to conventional ski-bobs,as now developed, of the construction resulting in the front ski-runnerbeing constantly disposed in substantially the same, substantiallyhorizontal plane across, and including the line or path of travel. Thisobjection results from the leading part of the rear skirunner beingsubstantially rigidly, only slightly yieldably, connected to the forwardarch of the frame of the vehicle (the steering post to the foot of whichthe forward skirunner is pivotally connected, having the foot of thesteering post connected thereto).

Thus there is considerable distance along the path of the travel thatthe ski-bob ski-runners together extend in substantially rigid straightline projection. This results in the convention ski-bob, in passing overundulations in the path of travel, tending to tear u the undulations asits real ski-runner passes thereover, The herein forms of invention eachsets out to provide a ski-bob with a substantially flexible or yieldableconnection between the leading part of the rear ski-runner and frame,whereby the ski-bob may follow the contour of an undulation ordepression, with the front ski-runner being advancing upwardly while therear ski-runner may be advancing downwardly or substantially on thelevel, or vice versa.

Referring now in detail to the drawings in which like reference numeralsare applied to like elements in the various views, a ski-bob is shown inFIG. 1 which discloses a generally informative form of the instantinvention, as comprised of a frame 11, a steering post 16 with a leafspring foot 13 about a pivot 40 which extends transversely of the pathof travel, as provided by a bracket 23 on the forward ski runner 24,disposed intermediate the toe or bow 24a and the rear or heel 24b of theski runner 24.

The steering post 16 has a cross-member 17 connected symmetricallyacross the top thereof to provide the handle bars, with grasps 18a and18b for the hands of the rider. The upper pivotal connection betweensteering post 16 and the forward arch 12a of the frame 11 is provided byan upper pivot by a pivot bolt 19 between a plate 20 extending forwardlyfrom the central frame part 1212, and an upper clip angle 21 on the rearface of the steering post 16 The lower pivotal connection, in line withthe upper pivotal connection 19, is provided by a pivot end 14 on thelower end of the forward frame arch 12a, extending into a bore 15a in alower clip angle 15 on the rear face of the steering post 16.

The frame 11 includes a rearwardly arched part 12c, extending rearwardlyand downwardly from the central frame part 12b, terminating in a leafspring transversely supported across the rear ski runner 31 by a rearsupport, pivot bracket 23a. The support bracket 23a is disposed upon therear ski runner 31 intermediate the heel 31b and the leading part or toe31a. The leading part 31a is shown connected to a hook 32, provided onthe rear face of the lower part of the forward arched frame part 12a, bya connector part 310, that has its forward end hooked over the hook 32and its rear part connected to the forward end of the leading part 31aby wire or strong elastic connection rings 33, whereby a yieldable orflexible connection is formed between the rear ski runner leading part31a and the lower end of the arched frame part 12a. Thus it can be seenthat, as travelling along a path or ice track, the forward ski runner 24may be advancing on the level or upwardly, whereas the rear ski runner31 may be advancing downwardly or on the level, or vice versa.

The seat 22 on which the rider sits is shown in FIG. 1 as being providedwith a clip angle or connection lug 26 to extend below the forward partof the seat to be adjustably connected in selective longitudinallyspaced apart positions with relation to a slot 26a in the frame part1211. Beneath the rear portion of the seat 22, a supporting shockabsorber has its upper end conventionally pivotally connected. The shockabsorber 25 is indicated of conventional design, with a spring, notshown, being compressed between the two inter-telescoped upper 4 andlower tubular members 28, 29 of the shock absorber 25.

As shown in FIGS. 2 and 3, a ski-bob 10', constructed generally afterthe manner of the ski-bob 10' shown in FIG. 1, is respectively, intransit over an undulation 27 in an ice track, between two depressions57, or in transit over a depression 57 between two undulations 27. Inthe first case the forward ski runner 24 is shown advancing on adownward slope 27a while the rear ski runner 31 is shown advancing on anupward slope 27b. In the second case the forward ski runner 24 is shownadvancing on an upward slope 27b while the rear ski runner 31 is shownadvancing on a downward slope 27a. In case the track, trail or path oftravel deviates from a straight course, or winds in plan view or uponthe ground, since the steering post 16 is pivotal with relation to theframe 11, the ski-bob may be steered to keep the front or forwardski-runner 24 pointed generally with a curve in the path, while the rearski runner 31 follows the direction of the path preceding the curve.Also, as to the ability of the ski-bob to follow undulations by virtueof the type of connection 31a and raised leading part 31a between thetrack contacting portions 31, 31b of the rear ski runner 31, and theforwardly arched frame part 12a, a part of the general path of travelmay be generally tracked by the forward ski runner 24, as sloped in onedirection while a part of the general path of travel to the rear thereofmay be generally tracked by the rear ski runner parts 31, 3112.

This results, as may be observed from a consideration of FIGS. 2 and 3,since the angle between steering post 16 and forward ski runner 24 andthe angle between the rearwardly arched frame part 120, and the rear skirunner parts 31, 31b may vary independently of each other. Thus, inpassing over any undulation, there is a much shorter in line extensionof ski runner to be topping and in part tearing up the crest of anundulation 27, or tearing it away by side swing, than in the case ofconventional types of ski-bob hereinabove described, with the leadingpart of the rear ski runner substantially rigidly connected to theforwardly arched part of the frame.

As shown in detail in FIG. 4, the lower tubular member 29 of theinter-telescoping members 28, 29 comprising the shock absorber 25, FIG.1, terminates in a yoke 30 with bifurcations 30a, 30b, which may bedisposed just outwardly of the re-curved or socket providing end of therear leaf spring 13, which, as aforesaid, comprises the lower end of therearwardly arched frame part 120. Thus, the pivot bolt a may be passedfirst through a part of the support bracket 23a, through a bifurcation30b, through the recurved leaf spring end 35 on the pad 34 disposed onbase 36 upon the ski-runner 31, thence through the other bifurcation30a, and finally through the other part of the support bracket 23a. Bythis construction, in addition to being mounted to pivot on a transversepivot, or to swing in a substantially vertical plane, with relation tothe rear ski runner 31, the frame 11 is in degree yieldably or flexiblyconnected to the rear ski runner 31.

Referring now to FIG. 5, the pivotal connection between the frame 11 andsteering post 16, FIG. 1, and also the pivotal connection between thelower leaf spring end 13 of the steering post 16, may be seen in detail.Thus the frame 11 may swing or pivot about an upwardly extending pivotaxis 14, 19', with relation to the steering post 16 and forward skirunner 24, and also the steering post 16 and forward ski runner 24 mayswing or pivot with relation to each other about an axis transverse tothe path of travel, and generally in a substantially vertical- 1yextending plane. In this construction pivot end 14 at the lower end ofthe forwardly arched frame part 12a of the frame 11 comprises upwardly ablock of rubber or resilient material 14d, which extends upwardly intothe lower end of the box section type frame member 12a, and which isaflixed thereto by nuts and bolts 39c, 39d.

At the lower end of the rubber block 14d, below the lower end of theframe part 12a, a metallic flange 14c has the rubber block 14d firmlyafiixed to the upper surface thereof, while a metallic post or pivotcore 14a extends centrally downwardly from the flange 14c and below thelevel of the upper leg of the aforesaid clip angle 15. A rubber orresilient sheath member 14b has a flanged head to fit between themetallic flange 14c and the upper surface of the upper leg of the clipangle 15, while a shank part extends centrally downwardly from theflange part of the sheath member 14b, and through a bore in the upperleg of the clip angle 15. The sheath member 14b is bored centrally toreceive the metallic shank or pivot core 14a therethrough. By thisconstruction the frame 11 has the lower member 14 of its pivot axis withrelation to the steering post 16, also yieldably or flexibly disposed indegree with relation to the steering post 16.

A block 37 of resilient material, as rubber, is shown with upper partinserted in the lower end of the steering post 16, and with the upperportion of the forward leaf spring 13 extending upwardly centrallythrough, or embedded in the rubber block 37, including a base part 37aprovided below the lower end of the steering post 16. The leaf spring 13extends upwardly within the lower end of the steering post 16 toterminate in a recurved or rounded upper end 38 formed to bear withspring pressure upon the inner, forward and rear surfaces of the boxtype section steering post 16. Nuts and bolts 39a, 3% are additionallyprovided, firmly to connect the block 37 and lower end of the steeringpost 16.

From the block base 37a the leaf spring 13 curves downwardly andforwardly to terminate in a recurved or socket providing, forward end35. Thus, a pivot bolt 40 may extend through a part of the bracket 23,and through the leaf spring pivot socket 35, as supported upon a pad 34upon a base 36 connected to the forward ski runner 24, by screws orbolts, not shown, and then through the other part of the bracket 23.

As shown in FIG. 6, a modification of the form of invention shown inFIGS. l-5, discloses a frame 11 with rearwardly arched part 110separately pivotally connected, without leaf spring, to a rear supportbracket 23a, from the pivotal connection of the shock absorber 25thereto, the shock absorber 25 being shown substantiallydiagrammatically. Forwardly of the upper, central section 11b of theframe 11, the forwardly arched frame part 11a is pivotally connected topivot about a substantially upstanding axis 14, 19, with relation to thesteering post 16, correspondingly as hereinabove described in regard toFIGS. 1-5. Also, the steering post 16 has a leaf spring 13 on its lowerend by which it is connected to pivot about a transverse pivot 40,comprising a transverse pivot axis, so that the steering post 16 andframe 11 con nected thereto, can pivot in a substantially vertical planewith relation to the forward ski runner 24, correspond ingly as shown inFIGS. 1-5.

The seat 22 is shown provided with a clip angle or lug 26a to extendtherebelow to be selectively connected to the frame part 11b by means ofnuts and bolts passed through longitudinally spaced apart holes 42a in aspine or plate 42 disposed centrally on top of the central frame part11b. The upper end of the shock absorber 25 is pivotally connected bymeans of a conventional transverse pivot providing arrangement, notshown, to the under side of the seat 22. Thus the seat 22 may beadjusted within range from full line to dotted line position shown inFIG. 6.

As shown in FIG. 7, the leading part 41a of the rear ski runner 41 has awing bolt 41d in the nose or forward end thereof so that the rear loopof an elastic cord 42 may be hooked thereunder, the ends of the cord 42being firmly sewed and connected together, as by strong threads 43. Theforward loop of the cord 42 is looped over a hood 32a that is providedon the rear face of the forwardly arched frame part 11a. Thus, as bestindicated in FIG. 6*, the elastic cord 42 comprises a resistablyyieldable, flexible connection between rear ski runner 41 and frame 11of the ski-bob 10a.

Making reference now to FIG. 8, a ski-bob 10b is shown that differs inone particular form preceding structures in that the steering post 16ahas no leaf spring lowermost, but makes a plain pivotal connection withthe forward ski runner 24 by means of a transverse pivot bolt 40a whichconnects it to a bracket 23d supported by the ski runner 24 just forwardof its heel 24b. As an additional variation the lower parts of therearwardly arch'ed frame part 11c and of a shock absorber 50 areconnected, successively, to forward and rear pivots provided by abracket 23b supported upon the rear ski runner 41 between the heel 41band leading part 410 thereof. The shock absorber 50, to be hereinbelowdescribed in detail, is shown including an upper tubular member 46a anda lower tubular member 46b terminating downwardly in a rod orcylindrical member 47 (by which pivotal connection is made to theaforesaid bracket 23b). The upper end of the shock absorber upper member46a provides a transverse pivot axis, not shown, to which is connected aconnector beneath the rear part of the seat 22. Also, a clamp 26b isprovided by which the forward end of the seat 22 is adjustably connectedto the central frame part or saddle 11b.

Also, in variation, an elastic cord 44 extends from a lug 230 on theupper, forward corner of the bracket 23b, through a guide opening 51 inthe leading part 410 of the rear ski runner 41, to a connection ring 45which extends rearwardly from the lower end portion of the forwardlyarched frame part 11a.

The elastic cord 44 must be of substantial strength and of predeterminedlimited elasticity, as it has to restrain the rear ski runner 41 tomaintain continuing contact with the ice or track over the length of thecentral and heel part 41b thereof, and thus must resist the tendency ofthe leading part 410 to kick upwardly responsive to bumps orirregularities in elevation occurring in the track.

Now considering FIG. 9, the ski-bob has a rearwardly arched frame partand shock absorber 50, to be hereinbelow described in detail, which areconnected to a bracket 23a upon the ski runner 41, correspondingly ashereinabove described in connection with the similar relationship ofthese elements in FIG. 8. However, it may be seen that the leading part41d is connected to the frame 11 in an entirely different manner, and inan entirely different direction, than hereinabove described in regard tothe rear ski runner leading parts 31a, 41a and 410 of the forms ofinvention shown in FIGS. 15, in FIGS. 6-7, and in FIG. 8. Thus in thisconstruction, a spring loaded connector 60 is shown having its lowermember 60b pivotally connected to a bracket 57b mounted on the uppersurface of the leading part 41d. Upwardly, the upper end of theconnector upper member or cylinder 60a is pivotally connected to abracket 57a provided on the under side of the frame central part orsaddle 11b forwardly of the saddle 22.

In this construction the spring, not shown in FIG. 9, may constantlyurge downwardly thus to constrain the leading part 41d of the rear skirunner 41 from flying upwardly responsive to any undulations orirregularities in elevation along the path of travel or ice track. Thiscan be an important feature except that some large object or obstructionthat could become insinuated between the forwardly arched frame 11a andthe leading part 41d of the rear ski runner 41, would have to be brokenup or pushed aside by the rear ski runner 41.

Referring now to FIG. 10, still another variation of skibob 10d isdisclosed in which the hold-down cord 44 and shock absorber 50 areemployed as hereinabove described with relation to the form of inventionshown in FIG. 8.

Additionally an elastic cord 44a is disposed to extend resilientlyyieldably and flexibly between a bracket 48b on the upper surface of therear ski runner leading part 410 and a bracket 48a on the under side ofthe central frame part or saddle 11b. Also, another elastic cord 44!) isshown extending between a bracket 49a on the upper rear part of therearwardly arched frame part 11C and a bracket 4912 on the upper surfaceof the heel 41b of the rear ski runner 41. Optionally, in place of theelastic cords 44a and 441) spring loaded connectors 60- may be mountedto extend in corresponding directions.

With this form invention the service exacted from the .elastic cord 44is particularized by counterpoising the forward and rearcounterbalancing cords 44a, 44b in part against each other. The rearcord 44!), in pulling upwardly on the rear ski heel 41b, tends to pivotthe leading part 41c downwardly, about the pivotal connection of theframe part 11c and rear ski runner 41 at the bracket 23b. Conversely,the forward cord 44a, in pulling upwardly on the rear ski leading part410, tends to pivot the heel 41b downwardly about the pivotal connectionof the frame part 11c and rear ski runner 41 at the bracket 23b. Ifspring loaded connectors 60 are employed in place of the COIdS 44a, 44b,the direction of urging is opposite- 1y, but the counterpoising ofelements that effectuate at least partial counterbalancing is the same.Thus, the cord 44 action is calibrated for its hold-down erect, aftertaking into consideration the degree of counterbalancing brought about,as hereinabove described.

The shock absorber 50, indicated partially diagrammatically, as providedbetween rear end of seat 22 and rear ski runner 41 in FIGS. 8, 9 and 10,is shown in detail in FIGS. 11 and 12. The upper member 46a is pivotallyconnected to a connection tube 63 which extends downwardly within therear, under portion of the seat 22, a transversely extending bolt 54passing through the tubing 63 from left to right, while the connectiontube or tubing 63 may pivot fore and aft with relation to the uppertubular member or cylinder 46a and about the pivot bolt 54. Thus, thetube 53 extends within a slot 52a in a metal block 52 in the upper endof the cylinder 45a, the metal block 52 being fixed in top of thecylinder 46a, right under the top closure 46b thereof, by means of thetransverse pivot bolt 54 passing therethrough on either side of, andoutwardly of the connection tubing 63.

The lower member or rod 47 of the shock absorber 50 is indicated inFIGS. 8, 9 and as having its lower end pivotally connected to atransverse pivot supported by the bracket provided just forward of theheel 41b of the rear ski runner 41. At its upper end the rod 47 isrigidly connected into a base flange 47a in which seats the lower end ofa lower cylindrical member 46b with upper end of dimension to telescopewithin the upper cylindrical member 46a. A transverse bolt 55b extendsacross, and connects the base flange 47a and the cylinder 46b. Above thebase flange 47a the lower cylindrical member 46b has left and rightslots 56a, 56b therein which extend upwardly for substantial distance,with the lower end of the upper cylindrical member 46a occluding theupper ends of the slots 56a, 56b for some distance. A bolt 55a extendsacross the lower end of the upper cylindrical member 46a and through theslots 56a, 56b just inwardly thereof.

Also a head 50a is insertable into the upper end of the lower tubularmember of cylinder 4612, the head 50a having a bore 50b centrallytherethrough. A transverse bore is provided through the head 50a abovethe top of the tubular member 461) and a connection pin 53 is insertedthrough the bore 50b to extend altogether within the head 50a and acrossthe central bore 5%. An elastic cord 540 extends resistably yieldablyand flexibly between, and around the bolts 55a, 5512. Also two elasticcords 54a, 54b extend resistably yieldably and flexibly between, andaround the pin 53 and bolt 55a, the elastic cord 54c being 8 disposedupon the bolt 55a between the elastic cords 54a, 54b.

Any extra force or weight distribution on the seat 22 that may result indownward urge on the upper tubular member 46a moves the bolt 55a nearerthe bolt 551;, so that the elastic cord 540 is permitted to contract,with resultant stretch of the elastic cords 54a, 54b as they yieldablyresist the bolt 55a moving away from the cross pin 53. Or conversely,any separative force or tendency of the upper cylindrical or tubularmember 46a to slide upwardly with relation to the lower tubular member461), results in the contraction of the two upper cords 54a, 54b, and inthe expansion or stretch of the lower cord 540. Thus, by properly sizingthe cords 54a, 54b and 540, wit-h proper distance between cross-pin 53and bolt 55b and with the proper predetermined occlusion of the slots56a, 56b by the upper tubular member 46a, it is possible to provide ashock absorber 50* that will properly respond to shock in bothdirection.

A spring-loaded connection member 60, shown in FIG. 9, may be describedin detail in relationship to FIG. 13; the shock-absorber 25 shown inFIGS. 1-3 and in FIG. 6 being similarly constructed. Thus a bracket 57bmounted on the forward upper surface of the leading part 41d of the rearski runner 41 may have the lower or rod member 6011 pivotally connectedthereto, as by a pivot pin c passed through the bracket 57b and throughthe rod member lower end 5817. The rod 6% extends upwardly into theupper tubular member or cylinder 60, and has a head or piston 59 on theupper end thereof, with an O-ring 59a therearound to bear yieldablysealably upon the inner surface of the cylinder 60a. Above the piston orhead 59 a spring 61 has upper end to bear upon an inner boss 58bcomprising part of an upper closure 58a, for the cylinder or uppermember 60a. The spring 61 is thus enclosed between the piston head 59and upper closure 58a, constantly to bear resistably, yieldably againstthe piston head 59. A bracket 57a is mounted on the under side of thecentral frame part 16b and the closure lug or cylinder top member 58aand this bracket 57a are relatively pivotally connected about atransverse pivot bolt 57b shown in FIG. 13. A lower closure 60d receivesthe piston rod 60b therethrough and closes the lower end of the cylinder60a. Thus the lower closure 60d may act as a stop against the spring 61urging the piston 59 out of the cylinder 6011 when frame and rear skirunner tend to be spread farthest apart.

In FIG. 14 a variation of yieldable or flexible connection between therearwardly arched frame part 110 and ski runner 31 is shown of a type tobe used in place of the form of connection shown in FIG. 4, and thisform has additional advantage in that the lower end of theshock-absorber between seat and rear ski runner may also be yieldably orflexibly connected. Refer to FIG. 4 where a rigid yoke makes connection.

In the form of connection shown in FIG. 1 a leaf spring 62 has itsforward end 63a affixed to the upper surface of the rear ski runner 31,as by a screw or screws 64. The leaf spring 62 is formed and temperednormally to provide the degree of arch for normal operating conditions.A lug or plate 63 upstands centrally from the top of the leaf springarch and the rearwardly arched frame part 116, terminating in a footpart 290, may be pivotally connected to the forward part of the lug 63,as by a conventional pivot pin. Also, the shock-absorber 25a, below theskibob seat, may provide a foot part 29b at the lower end of the lowershockabsorber member 29a which may be pivotally connected to the rearpart of the plate or lug 63 by a conventional pivot pin. Rearwardly ofthe leaf spring arch the leaf spring is flattened with rear portion 63bto slide through a keeper or hold-down plate 65 installed across theleaf spring on the heel 31b of the rear ski runner 31.

Thus, when frame and rear ski runner 31 tend to draw apart in service,as on an ice track, the leaf spring arches further upwardly as its rearportion 63b slides forwardly in the keeper plate 65. Or, when the frameand rear ski 4 runner 31 tend to draw closer together in service, theleaf spring arch is flattened as the leaf spring rear portion 63b slidesrearwardly in the keeper plate 65. Under the above usages, theshock-absorber lower member 29a thus moves with the leaf spring arch inaccordance with the respective conditions set forth. It should bepointed out that a corresponding arched leaf spring connection may beemployed between steering post and forward ski runner in place of thetype of leaf spring connection 13 shown in detail in FIG. 5.

The various separate features as to connection between steering post andforward ski runner, connection between rear ski runner leading part andframe, connection between frame and rear ski runner, shock-absorberconstruction and connection, and rear ski runner hold-down andcounter-balancing, may be used interchangeably and in variouscombinations, all falling within the spirit of the invention, which isfurther presented in the appended claims.

What is claimed is:

1. A ski-bob comprising a frame with an integrally formed forwardly anddownwardly extending forward part, an upper central saddle part with aseat thereon and a rearwardly and downwardly extending rear part, aforward ski runner with an upwardly turned leading part, a steering postpivotally connected to said frame forward part and having a lower endportion means pivotally connecting said forward ski runner to saidsteering post lower end portion so that it is relatively pivotal thereonin an upright plane that extends through said steering post and saidforward ski runner, a rear ski runner positioned longitudinally in linebehind said front ski runner and having an upwardly turned leading part,means located to the rear of its said leading part pivotally connectingsaid rear ski to said frame rear part so that said rear ski runner ismovable relative to said frame in an upright plane that extends throughsaid frame and said rear ski runner, and resiliently extensible meansyieldably connecting said rear ski runner leading part to said forwardframe part, whereby said ski-bob in transit may closely follow a trackthat may be undulatory in elevation and curved in plan view.

2. A ski-bob as claimed in claim 1 wherein said resiliently extensiblemeans yieldably connecting said rear ski runner leading part to saidframe comprises an elastic cord between said leading part and said frameforward part.

3. A ski-bob as claimed in claim 1 wherein said resiliently extensiblemeans yieldably connecting said rear ski runner leading part to saidframe comprises an intertelescoping, coil spring enclosing, tubularassembly.

4. A ski-bob as claimed in claim 1 wherein said resiliently extensiblemeans yieldably connecting said rear ski runner leading part to saidframe comprises an elastic cord having a rear end supported on saidframe above said rear ski runner rearwardly of said leading part, andpassing forwardly through the upper portion of said leading part and afront end connected forwardly to the lower portion of said frame forwardpart.

5. A ski-bob as claimed in claim 4 which additionally includes elasticcords in counterpoised relationship between the leading part of saidrear ski runner and said saddle part and between the rear portson ofsaid rear ski runner and said frame rear part.

6. A ski-bob as claimed in claim 1 wherein said means for pivotallyconnecting the lower end of said steering post to said forward skirunner includes a yieldable leaf spring.

7. A ski-bob as claimed in claim 6 wherein said leaf spring is curvedand has an upper end portion fixed to said steering post and a lower endportion pivotally connected to said forward ski runner.

8. A ski-bob as claimed in claim 1 wherein said means connecting theframe rear part to said rear ski runnecomprises a leaf spring having anupwardly arched por tion fixed to said rear frame part.

9. A ski-bob as claimed in claim 1 including a shockabsorberinterconnecting the rear portion of said seat and said rear ski runneradjacent a said frame rear part, said shock-absorber being comprised ofupper and lower, inter-telescoping tubular members connected by upperand lower elastic cord means, whereby upper elastic cord means stretchupon downward movement of said upper tubular member, and lower elasticcord means stretch upon upward movement of said upper tubular means.

References Cited UNITED STATES PATENTS 1,516,941 11/1924 Winn 280' 162,17 6,397 10/ 1939 Flanders 280-16 2,354,627 7/ 1944 Wheeler 2-80--162,479,674 8/ 1949 Elliot 280-16 FOREIGN PATENTS 385,637 3 1965Switzerland.

87,487 7/ 1966 France. 443,931 2/ 1968 Switzerland.

LEO FRIAGLIA, Primary Examiner R. R. SONG, Assistant Examiner

